Inspector Morse: The Daughters of Cain (1996)

Felix McClure, an Oxford University professor, is stabbed to death in his college study. Not only was he an expert in his field but he was one of the University's key fund-raisers. The investigation focuses on Brooks, a one-time cleaner for McClure who quit his college job abruptly after a student, Mathew Rodway, jumped out of a college window high on drugs. When Morse learns that Brooks' daughter was the object of affection for both Rodway and another student, he has another possible suspect. Brooks' wife also worked for one of McClure's friends and Morse uncovers a conspiracy that he may not be able to prove.